TimeUtils.java revision 0574ca37da4619afe4e26753f5a1b4de314b6565 
1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.support.v4.util;
18
19import java.io.PrintWriter;
20
21/**
22 * Helper for accessing features in {@link android.util.TimeUtils}
23 * introduced after API level 4 in a backwards compatible fashion.
24 *
25 * @hide
26 */
27public class TimeUtils {
28    /** @hide Field length that can hold 999 days of time */
29    public static final int HUNDRED_DAY_FIELD_LEN = 19;
30
31    private static final int SECONDS_PER_MINUTE = 60;
32    private static final int SECONDS_PER_HOUR = 60 * 60;
33    private static final int SECONDS_PER_DAY = 24 * 60 * 60;
34
35    private static final Object sFormatSync = new Object();
36    private static char[] sFormatStr = new char[HUNDRED_DAY_FIELD_LEN+5];
37
38    static private int accumField(int amt, int suffix, boolean always, int zeropad) {
39        if (amt > 99 || (always && zeropad >= 3)) {
40            return 3+suffix;
41        }
42        if (amt > 9 || (always && zeropad >= 2)) {
43            return 2+suffix;
44        }
45        if (always || amt > 0) {
46            return 1+suffix;
47        }
48        return 0;
49    }
50
51    static private int printField(char[] formatStr, int amt, char suffix, int pos,
52            boolean always, int zeropad) {
53        if (always || amt > 0) {
54            final int startPos = pos;
55            if ((always && zeropad >= 3) || amt > 99) {
56                int dig = amt/100;
57                formatStr[pos] = (char)(dig + '0');
58                pos++;
59                amt -= (dig*100);
60            }
61            if ((always && zeropad >= 2) || amt > 9 || startPos != pos) {
62                int dig = amt/10;
63                formatStr[pos] = (char)(dig + '0');
64                pos++;
65                amt -= (dig*10);
66            }
67            formatStr[pos] = (char)(amt + '0');
68            pos++;
69            formatStr[pos] = suffix;
70            pos++;
71        }
72        return pos;
73    }
74
75    private static int formatDurationLocked(long duration, int fieldLen) {
76        if (sFormatStr.length < fieldLen) {
77            sFormatStr = new char[fieldLen];
78        }
79
80        char[] formatStr = sFormatStr;
81
82        if (duration == 0) {
83            int pos = 0;
84            fieldLen -= 1;
85            while (pos < fieldLen) {
86                formatStr[pos] = ' ';
87            }
88            formatStr[pos] = '0';
89            return pos+1;
90        }
91
92        char prefix;
93        if (duration > 0) {
94            prefix = '+';
95        } else {
96            prefix = '-';
97            duration = -duration;
98        }
99
100        int millis = (int)(duration%1000);
101        int seconds = (int) Math.floor(duration / 1000);
102        int days = 0, hours = 0, minutes = 0;
103
104        if (seconds > SECONDS_PER_DAY) {
105            days = seconds / SECONDS_PER_DAY;
106            seconds -= days * SECONDS_PER_DAY;
107        }
108        if (seconds > SECONDS_PER_HOUR) {
109            hours = seconds / SECONDS_PER_HOUR;
110            seconds -= hours * SECONDS_PER_HOUR;
111        }
112        if (seconds > SECONDS_PER_MINUTE) {
113            minutes = seconds / SECONDS_PER_MINUTE;
114            seconds -= minutes * SECONDS_PER_MINUTE;
115        }
116
117        int pos = 0;
118
119        if (fieldLen != 0) {
120            int myLen = accumField(days, 1, false, 0);
121            myLen += accumField(hours, 1, myLen > 0, 2);
122            myLen += accumField(minutes, 1, myLen > 0, 2);
123            myLen += accumField(seconds, 1, myLen > 0, 2);
124            myLen += accumField(millis, 2, true, myLen > 0 ? 3 : 0) + 1;
125            while (myLen < fieldLen) {
126                formatStr[pos] = ' ';
127                pos++;
128                myLen++;
129            }
130        }
131
132        formatStr[pos] = prefix;
133        pos++;
134
135        int start = pos;
136        boolean zeropad = fieldLen != 0;
137        pos = printField(formatStr, days, 'd', pos, false, 0);
138        pos = printField(formatStr, hours, 'h', pos, pos != start, zeropad ? 2 : 0);
139        pos = printField(formatStr, minutes, 'm', pos, pos != start, zeropad ? 2 : 0);
140        pos = printField(formatStr, seconds, 's', pos, pos != start, zeropad ? 2 : 0);
141        pos = printField(formatStr, millis, 'm', pos, true, (zeropad && pos != start) ? 3 : 0);
142        formatStr[pos] = 's';
143        return pos + 1;
144    }
145
146    /** @hide Just for debugging; not internationalized. */
147    public static void formatDuration(long duration, StringBuilder builder) {
148        synchronized (sFormatSync) {
149            int len = formatDurationLocked(duration, 0);
150            builder.append(sFormatStr, 0, len);
151        }
152    }
153
154    /** @hide Just for debugging; not internationalized. */
155    public static void formatDuration(long duration, PrintWriter pw, int fieldLen) {
156        synchronized (sFormatSync) {
157            int len = formatDurationLocked(duration, fieldLen);
158            pw.print(new String(sFormatStr, 0, len));
159        }
160    }
161
162    /** @hide Just for debugging; not internationalized. */
163    public static void formatDuration(long duration, PrintWriter pw) {
164        formatDuration(duration, pw, 0);
165    }
166
167    /** @hide Just for debugging; not internationalized. */
168    public static void formatDuration(long time, long now, PrintWriter pw) {
169        if (time == 0) {
170            pw.print("--");
171            return;
172        }
173        formatDuration(time-now, pw, 0);
174    }
175}
176